This invention relates to window assemblies having tiltable sashes, and more particularly to a new and improved form of tilt latch for releasably retaining a tiltable window sash in a window frame.
Windows having sashes that slide vertically in fixed frames are sometimes arranged to enable the sash to rotate or tilt inwardly (about an axis generally coincident with the bottom rail of the sash), for example to facilitate cleaning the outside glass surface of the window. To this end, the sash is typically provided with a pair of latches, mounted at the top of the sash respectively adjacent the sides thereof, and designed to ride in vertical recesses formed in the two sides of the frame so as to retain the sash in its path of sliding movement in the frame, the latches being manually disengageable from the frame recesses to release the sash for tilting with respect to the frame.
Latches having the above-described function (commonly termed tilt latches) are conventionally constituted of two injection-molded plastic parts and a resilient biasing element such as a spring. Thus, an illustrative conventional tilt latch includes a base member mountable on the top corner of the window sash, a slide member disposed in the base member for sliding movement into and out of a position in which it is inserted in a window frame recess, and a coil spring for biasing the latch member into the inserted position while permitting the slide member to be moved manually against the spring force to a retracted position in which the slide member is clear of the window frame.
Various difficulties have heretofore been encountered with conventional tilt latches of the type described. For instance, it has been necessary for the installer to asssemble the latch components before mounting the latch on a window sash. This is not only inconvenient for the installer but may lead to loss of or damage to parts of the latch assembly. In addition, known latches have been undesirably large in size, and the location of fasteners for securing such latches to a window sash has been dictated by considerations of latch design which have prevented attainment of optimum strength or security of attachment.